ILLUMINATION SYSTEM EMPLOYING AN ARRAY OF MICROPRISMS

摘要

An optical illumination system comprising a waveguide (16) that accepts light generated by a diffuse light source 114) and transmits the light via total internal reflection. Attached on one face of the waveguide is am array of microprisms (90) with each microprism (90) having a light input surface (92) parallel to a light output surface (94) and at least two sidewalls (96 98) tilted at am angle from the direction normal to the surface of the waveguide (16) such that light escapes from the waveguide, reflects off the tilted sidewalls (96, 98) and emerges from the microprism (90) as a spatially directed light source. An array of microlenses (80) may be positioned to accept the output of the microprisms (90) so that the light exiting from the microlenses (80) is a substantially collimated light source. The optical illumination system is advantageous for any application that requires a non diffuse or substantially collimated that is both energy efficient and contained in a low profile assembly.